Development and predictive effects of eating disorder risk factors during adolescence: Implications for prevention efforts.

OBJECTIVE: Although several prospective studies have identified factors that increase risk for eating disorders, little is known about when these risk factors emerge and escalate, or when they begin to predict future eating disorder onset. The objective of this report was to address these key research gaps.
METHOD: Data were examined from a prospective study of 496 community female adolescents (M = 13.5, SD = 0.7 at baseline) who completed eight annual assessments of potential risk factors and eating disorders from preadolescence to young adulthood.
RESULTS: Three variables exhibited positive linear increases: Perceived pressure to be thin, thin-ideal internalization, and body dissatisfaction; three were best characterized as quadratic effects: dieting (essentially little change); negative affectivity (overall decrease), and BMI (overall increase). Elevated body dissatisfaction at ages 13, 14, 15, and 16 predicted DSM-5 eating disorders onset in the 4-year period after each assessment, but the predictive effects of other risk factors were largely confined to age 14; BMI did not predict eating disorders at any age. DISCUSSION: The results imply that these risk factors are present by early adolescence, although eating disorders tend to emerge in late adolescence and early adulthood. These findings emphasize the need for efficacious eating disorder prevention programs for early adolescent girls, perhaps targeting 14-year olds, when risk factors seem to be most predictive. In early adolescence, it might be fruitful to target girls with body dissatisfaction, as this was the most consistent predictor of early eating disorder onset in this study.